Silybin derivative as well as preparation method and application thereof

Abstract

The invention relates to a silibinin derivative as well as a preparation method and application thereof, and belongs to the technical field of chemistry. The invention relates to a silibinin derivative, which is 6-sulfonated silibinin sodium sulfonate, the chemical name of the silibinin derivative is 2, 3-dihydro-3-(4-hydroxy-3-methoxyphenyl)-2-hydroxymethyl-6-(3, 5, 7-trihydroxy-4-oxo benzopyran-2-yl) benzodioxane-6-sodium sulfonate, the molecular formula of the silibinin derivative is C25H21NaO13S, and the molecular weight of the silibinin derivative is 584.49. Sulfonic acid groups with hydrophilicity are introduced into different parts of the silibinin to prepare different types of silibinin sodium sulfonate, so that the solubility of the silibinin sodium sulfonate in water is enhanced, the pharmacokinetic characteristics of the silibinin are improved from the pharmacokinetic level, the affinity and biological activity of the silibinin to organisms are improved, and the application prospect of the silibinin sodium sulfonate is widened. The compound is further prepared into an injection for clinical treatment, and has important clinical drug treatment value.

Description

Technical Field

[0001] This invention relates to a silymarin derivative, its preparation method and application, belonging to the field of chemical technology. Background Technology

[0002] Silybin, chemical structural formula Milk thistle is a natural active ingredient extracted from milk thistle. Due to its multiple pharmacological effects, including antioxidant, anti-inflammatory, and anti-liver fibrosis properties, it is widely used in liver protection treatment. However, the inherent low water solubility and poor intestinal absorption of this compound result in extremely poor oral bioavailability, which has become a major bottleneck restricting its clinical efficacy, especially in the treatment of moderate to severe liver disease. To overcome this deficiency, existing technologies mainly focus on dosage form improvement strategies such as salt formation (e.g., meglumine salt) or the preparation of complexes (e.g., phospholipid complexes). However, these methods have limited effects on improving water solubility and bioavailability, and still cannot achieve injection administration, making it difficult to meet the stringent requirements for drug onset speed and blood drug concentration in the treatment of acute and severe liver diseases.

[0003] Furthermore, silybin molecules possess multiple modifiable sites, but current technologies lack methods for efficiently and selectively performing hydrophilic modifications at specific sites. In particular, precise sulfonation at the 6-position of benzodioxane to obtain a single, well-defined, highly soluble derivative remains a significant technical challenge. Summary of the Invention

[0004] The purpose of this invention is to address the deficiencies of existing technologies by proposing a silymarin derivative, its preparation method, and its application, thereby achieving precise sulfonation of benzodioxane at the 6-position and meeting the requirements for injection administration.

[0005] The core objective of this invention is to overcome the application limitations caused by the inherent physicochemical properties of silybin, avoiding simply repeating existing dosage form improvement efforts. Based on this objective, this invention solves the technical problem through the following technical solution: First, it provides a silybin derivative with a novel structure and fundamentally improved water solubility, whose solubility should meet the requirements for injection administration. Specifically, it is a silybin derivative, namely sodium 6-sulfonated silybin sulfonate, chemically named sodium 2,3-dihydro-3-(4-hydroxy-3-methoxyphenyl)-2-hydroxymethyl-6-(3,5,7-trihydroxy-4-oxobenzopyran-2-yl)benzodioxane-6-sulfonate, with the molecular formula C2. 25 H 21 NaO 13 S, with a molecular weight of 584.49, has the chemical structure shown in general formula (II). .

[0006] The present application experimentally finds that the benzene rings at positions 6, 8, 21 and 22 in the molecular structure of silymarin are all potential sulfonation reaction sites. However, due to the differences in the electronic effect and spatial configuration of the functional groups such as phenolic hydroxyl groups adjacent to each reaction site, the sulfonation reaction activity thereof presents significant differences. Therefore, by systematically screening sulfonating agent combinations with different reaction activities and precisely regulating the reaction conditions, selective sulfonation for specific positions is realized, thereby directionally synthesizing sulfonated products with different substitution modes. The method of the present application preferentially causes sulfonation at the 6-position of the benzodioxane ring, and has less by-products.

[0007] To realize precise sulfonation at the 6-position of the benzodioxane ring, the present application further provides a preparation method of a silymarin derivative, comprising the following steps: In the first step, selective sulfonation reaction, silymarin is dispersed in an organic solvent, a sulfonating agent is added, and the reaction is carried out at 40-80℃ for 5-12 hours to cause sulfonation at the 6-position of the benzodioxane ring; In the second step, post-treatment and hydrolysis, after the reaction is completed, the reaction is quenched with a saturated sodium chloride solution, the aqueous phase is separated, dilute sulfuric acid is added, and hydrolysis is carried out at 40-60℃ to remove the sulfate group; In the third step, salt formation and refinement, the pH of the hydrolysis solution is adjusted to 5-6, extraction is carried out with acetonitrile, after concentration, salt precipitation is carried out with a saturated sodium chloride solution, and solid is obtained, which is recrystallized with isopropanol to obtain high-purity 6-sulfonated silymarin sodium sulfonate.

[0008] The reaction route is as follows:

[0009] In the first step of the above method, the organic solvent is acetonitrile, dioxane or pyridine.

[0010] The sulfonating agent is sulfamic acid, sulfur trioxide-pyridine complex or phosphorus pentoxide / sulfuric acid system.

[0011] The present application further provides a pharmaceutical composition comprising a therapeutically effective amount of 6-sulfonated silymarin sodium sulfonate and a pharmaceutically acceptable carrier.

[0012] The dosage form of the composition is an injection. The injection is a freeze-dried powder injection or an injection solution. The water solubility of the derivative is ≥100 mg / ml, and it is particularly suitable for intravenous or intramuscular injection.

[0013] The present application further provides the use of the silymarin derivative or the pharmaceutical composition in the preparation of a medicament for treating liver diseases.

[0014] In the above use, the liver disease is at least one of metabolic associated fatty liver disease (MAFLD), metabolic associated steatohepatitis (MASH), liver fibrosis, liver cirrhosis, drug-induced or alcohol-induced liver injury, and other acute or chronic liver diseases closely related to oxidative stress and inflammation.

[0015] The present application introduces a hydrophilic sulfonic acid group into different parts of silybin to prepare different types of silybin sodium sulfonate, thereby enhancing its solubility in water, improving its pharmacokinetic characteristics from the pharmacokinetic level, improving its affinity and biological activity to the organism, and then preparing an injection for clinical treatment, which has great clinical drug treatment value. Compared with the prior art, the present application has made the following breakthroughs and significant benefits: site innovation, superior properties: for the first time, the precise sulfonation of the benzodioxane 6-position of silybin is successfully achieved, and a new derivative with clear structure is obtained. The derivative completely solves the solubility problem of silybin, and the solubility is increased by more than 2000 times, which lays a key foundation for the development of injection forms. Efficient process, good selectivity: the preparation method of the present application significantly improves the selectivity of 6-position sulfonation by means of the ingenious combination of reagents and conditions, the reaction time is shortened to 5-12 hours, the by-products are less, the post-treatment is simple, the yield is good (76% in Example 1), and it is more suitable for industrial production. The pharmacokinetic characteristics are fundamentally improved: the absolute bioavailability of injection administration can reach nearly 100%, which ensures that the drug can quickly and completely enter the systemic circulation, thereby providing strong support for the emergency and treatment of severe liver disease. Enhanced pharmacological activity: animal tests show that the product is superior to silybin in improving liver steatosis, inhibiting inflammatory infiltration, and reversing fibrosis, indicating that it has better clinical treatment potential. Excellent preparation performance: based on its high solubility and stability, it can be conveniently prepared into a freeze-dried powder injection, the product quality is controllable, the storage and transportation are convenient, and the clinical use is convenient. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 MS spectrum of 6-silybin sodium sulfonate.

[0017] Figure 2 1H NMR spectrum of 6-silybin sodium sulfonate.

[0018] Figure 3 IR (KBr) spectrum of 6-silybin sodium sulfonate.

[0019] Figure 4 UV spectrum of 6-silybin sodium sulfonate. DETAILED DESCRIPTION

[0020] Example 1 This example prepares 6-silybin sodium sulfonate according to the following steps: First step, in the reaction bottle, add 100g of Silybinin, 100g of sulfamic acid, 140g of sodium bisulfate monohydrate and 1000ml of acetonitrile, stir evenly. Slowly add 100ml of concentrated sulfuric acid at room temperature, then increase the oil bath temperature to 70-80°C, stir for 10-12 hours, stop the reaction after monitoring the reaction progress by TLC.

[0021] Second step, cool the reaction solution to room temperature, add 10 times the volume of saturated sodium chloride solution, stir for 1 hour, then stand and separate. Take the aqueous phase, add an equal volume of 10% dilute sulfuric acid, hydrolyze at 40°C for 5-10 hours, monitor the complete hydrolysis by HPLC.

[0022] Third step, adjust the pH of the hydrolysis solution to 5.5 with 20% sodium hydroxide solution, extract with acetonitrile 3 times, combine the acetonitrile phase, and concentrate to dryness under reduced pressure. Add saturated aqueous sodium chloride solution to the residue, stir to precipitate the solid, and filter. Desalt the solid with anhydrous ethanol, evaporate the ethanol to obtain the crude product. Recrystallize the crude product with isopropanol 2 times, dry to obtain 76g of white solid of 6-silybinin sodium sulfonate, with a yield of 76% and an HPLC purity of >98.5%.

[0023] Example 2 This example prepares 6-silybinin sodium sulfonate according to the following steps: First step, in the reaction bottle, add 110g of sulfamic acid, 50g of sodium bisulfate monohydrate, 900ml of dioxane solvent, 100ml of acetonitrile, and 50ml of concentrated sulfuric acid. Stir at room temperature for 30 minutes, then slowly add 200g of Silybinin and stir evenly. Increase the temperature to 70-80°C and stir for about 5-10 hours. Stop the reaction after monitoring the reaction progress by TLC.

[0024] Second step, cool the reaction solution to room temperature, add 10 times the volume of saturated sodium chloride solution, stir for 1 hour, then stand and separate. Take the aqueous phase, add an equal volume of 10% dilute sulfuric acid, hydrolyze at 40°C for 5-10 hours, monitor the complete hydrolysis by HPLC.

[0025] Third step, adjust the pH of the hydrolysis solution to 5.5 with 20% sodium hydroxide solution, extract with acetonitrile 3 times, combine the acetonitrile phase, and concentrate to dryness under reduced pressure. Add saturated aqueous sodium chloride solution to the residue, stir to precipitate the solid, and filter. Desalt the solid with anhydrous ethanol, evaporate the ethanol to obtain the crude product. Recrystallize the crude product with isopropanol 2 times, dry to obtain 96g of solid of 6-silybinin sodium sulfonate, with a yield of 48% and an HPLC purity of >98.5%.

[0026] Example 3 This example prepares 6-silybinin sodium sulfonate according to the following steps: First step, in the reaction bottle, add 60g of phosphorus pentoxide, 1000ml of acetonitrile solvent, drop 30ml of concentrated sulfuric acid under stirring, stir at room temperature for 30 minutes, then slowly add 100g of water flycine, continue to stir the reaction solution, react at 40-50℃ for about 5-10 hours, stop the reaction after monitoring the reaction process by TLC.

[0027] Second step, cool the reaction solution to room temperature, add 10 times the volume of saturated sodium chloride solution, stir for 1 hour, then stand and separate. Take the water phase, add equal volume of 10% dilute sulfuric acid, hydrolyze at 40℃ for 5-10 hours, monitor the complete hydrolysis by HPLC.

[0028] Third step, adjust the pH of the hydrolysis solution to 5.5 with 20% sodium hydroxide solution, extract with acetonitrile for 3 times, combine the acetonitrile phase, and concentrate to dryness under reduced pressure. Add saturated sodium chloride aqueous solution to the residue, stir to precipitate the solid, and filter. The solid is desalted with anhydrous ethanol, and evaporate the ethanol to obtain the crude product. Recrystallize the crude product with isopropanol for 2 times, dry to obtain 6-water flycine sodium sulfonate solid 30g, with a yield of 33%, and HPLC purity >98.5%.

[0029] Example 4 This example is prepared according to the following steps to prepare 6-water flycine sodium sulfonate: First step, in the reaction bottle, add 45g of sulfur trioxide pyridine complex, 500ml of pyridine solvent, 50g of water flycine, stir at room temperature for 30 minutes, then slowly drop 10ml of concentrated sulfuric acid, stir evenly, and heat to 40-50℃ for about 5-10 hours, stop the reaction after monitoring the reaction process by TLC.

[0030] Second step, cool the reaction solution to room temperature, add 10 times the volume of saturated sodium chloride solution, stir for 1 hour, then stand and separate. Take the water phase, add equal volume of 10% dilute sulfuric acid, hydrolyze at 40℃ for 5-10 hours, monitor the complete hydrolysis by HPLC.

[0031] Third step, adjust the pH of the hydrolysis solution to 5.5 with 20% sodium hydroxide solution, extract with acetonitrile for 3 times, combine the acetonitrile phase, and concentrate to dryness under reduced pressure. Add saturated sodium chloride aqueous solution to the residue, stir to precipitate the solid, and filter. The solid is desalted with anhydrous ethanol, and evaporate the ethanol to obtain the crude product. Recrystallize the crude product with isopropanol for 2 times, dry to obtain 6-water flycine sodium sulfonate solid 30g, with a yield of 33%, and HPLC purity >98.5%.

[0032] The obtained product is analyzed by mass spectrometry ( Figure 1 ), nuclear magnetic resonance ( Figure 2 ), infrared spectroscopy ( Figure 3 ), and ultraviolet spectroscopy ( Figure 4The structure was confirmed as 6-oxymatrine sodium sulfonate (II) by the characteristic peaks at 203 nm and 286 nm.

[0033] Example 5 This example is the preparation process of 6-oxymatrine sodium sulfonate lyophilized powder injection, specifically: taking 50 g of 6-oxymatrine sodium sulfonate prepared in Example 1, dissolving it in 1000 ml of water for injection together with 100 g of mannitol, stirring until completely dissolved, adjusting the pH to 7.0-7.5 with 0.1M NaOH solution. The solution was filtered through a 0.22 μm microporous filter. Filling into a Westlin bottle, 2 ml per bottle, containing 100 mg of main drug. Freeze-drying to obtain white loose block, and then sealing, to obtain the lyophilized powder injection.

[0034] Example 6 Solubility and stability test Solubility: According to the method described in the Chinese Pharmacopoeia (2025 edition four volumes) under the fifteenth property, the solubility of 6-oxymatrine sodium sulfonate (II) in water at 25℃ is greater than 100 mg / ml, while the solubility of oxymatrine raw material is less than 0.05 mg / ml.

[0035] Time (month) Appearance PH Solubility Content (%) 0 Light yellow powder 7.12 Easily soluble 98.6 1 Light yellow powder, no obvious change 7.15 Easily soluble 98.4 2 Light yellow powder, no obvious change 7.11 Easily soluble 98.7 3 Light yellow powder, no obvious change 7.09 Easily soluble 98.2 6 Light yellow powder, no obvious change 7.07 Easily soluble 98.3

[0036] In addition to the above embodiments, the present application can have other embodiments. Any technical solution formed by equivalent substitution or equivalent transformation falls within the scope of protection required by the present application.

Claims

1. A silybinin derivative, characterized by: The derivative is 6-sulfated silybinin sodium sulfonate, chemical name is 2,3-dihydro-3-(4-hydroxy-3-methoxyphenyl)-2-hydroxymethyl-6-(3,5,7-trihydroxy-4-oxo-chromen-2-yl)benzodioxane-6-sulfonic acid sodium, molecular formula is C 25 H 21 NaO 13 S, molecular weight is 584.49, and its chemical structure is shown in general formula (II), .

2. A method for preparing a silybin derivative, characterized by, The method comprises the following steps: The first step is a selective sulfonation reaction, in which the aescin is dispersed in an organic solvent, a sulfonating agent is added, and the reaction is carried out at 40-80℃ for 5-12 hours, so that sulfonation occurs at the 6-position of the benzodioxane ring; The second step is post-treatment and hydrolysis, in which after the reaction is completed, the reaction is quenched with a saturated sodium chloride solution, the aqueous phase is separated, dilute sulfuric acid is added, and hydrolysis is carried out at 40-60℃ to remove the sulfate group; The third step is salification and purification, in which the pH of the hydrolysis solution is adjusted to 5-6, acetonitrile is used for extraction, after concentration, a saturated sodium chloride solution is added for salting-out, and solidification is carried out, followed by recrystallization with isopropanol, so that high-purity 6-sulfonated aescin sodium sulfonate is obtained.

3. The method for preparing the silymarin derivative according to claim 2, characterized in that: In the first step, the organic solvent is acetonitrile, dioxane or pyridine.

4. The method for preparing the silymarin derivative according to claim 2, characterized in that: In the first step, the sulfonating agent is sulfamic acid, sulfur trioxide-pyridine complex or phosphorus pentoxide / sulfuric acid system.

5. A pharmaceutical composition, characterized by: The composition comprises a therapeutically effective amount of 6-sulfonated aescin sodium sulfonate and a pharmaceutically acceptable carrier.

6. The pharmaceutical composition according to claim 5, wherein: The dosage form of the composition is an injection.

7. The pharmaceutical composition according to claim 6, characterized in that: The injection is a lyophilized powder injection or an injection solution.

8. Use of the aescin derivative of claim 1 or the pharmaceutical composition of claim 5 in the preparation of a medicament for treating liver diseases.

9. Use according to claim 8 for the manufacture of a medicament for the treatment of liver diseases, characterized in that: The liver disease is at least one of metabolic associated fatty liver disease (MAFLD), metabolic associated steatohepatitis (MASH), liver fibrosis, liver cirrhosis, drug-induced or alcohol-induced liver injury, and other acute or chronic liver diseases closely related to oxidative stress and inflammation.

Images